So a while back I had to shift steam and other games onto an external hard drive as my main drive was simply too full. Now I've recently been downloading games from gog into this external drive and then installing them into the drive itself. However I've noticed that the install times are taking a very long time and some games (such as Jade Empire) are only installing part way before stalling for ages and then running out of memory.

It sounds like there's some kind of bottleneck happening and maybe something that requires cleaning out/deleting/flushing/resetting to clear it so that I can continue. The drive itself has over 300GB of space left on itself.

So has anyone any idea or do I have to install things from my primary drive onto the external to avoid this problem?

usb 3.0?

Far as I know USB 2.0

Maybe take out the hdd from the external and connect it via sata/ide to your computer. Should work much better than USB.

you may want to consider defragging that hard drive, if you use a third-party defragger check to see if there is an "optimize" option. unless it's one of those "built as" external drives & not just a encosure that the user adds the HD

High chance that's your problem.

First of all, I would be very careful installing anything on an external drive. If you disconnect it (or it loses power) while data is being transferred, there's a chance that the entire drive becomes inaccessible. I had this happen with one of my drives - disconnecting it at the wrong moment corrupted the partition table and the directory - an entire 2 Terabyte partition was lost, and after trying out everything else, I had to spend 70€ on a professional recovery tool to get my files back.

This is not so much a problem when you use the drive only for archiving, because then you can easily control when there's any data transfer going on. Once software is installed on that drive, it gets much more complicated. Especially when that software is Steam, which tends to do access its libraries, and downloads and updates stuff, in the background. If there is anything else on your internal drive that is just "data" - movies, music that you don't listen to every day, photos, etc. - then you'd run a much lower risk of data loss by putting that data on the external drive, and installing your games on the internal drive.

Now, regarding your question:

External drives have slower connections than internal ones. By downloading the installer to the external drive, you a) might get a slower download (depending on your Internet connection), and b) double the amount of data that needs to be transferred across that slow connection when you install a game. You may also run into performance problems when playing the games, though for GOG classics it shouldn't matter. If there is absolutely no way to install the games on the internal drive, then I would at least download the installers to the internal drive first, run them from there, and (if you want to keep them) move them to the external drive afterwards.

Thanks for the info!

The drive is fairly safe from being disconnected randomly at least in a physical sense though you raise a good point about steam constantly wanting to chat to its library (typically though if I'm not using steam its switched off anyway). I'd like to move it all internal and I've started earmarking and saving up toward a full computer upgrade - just at the present the main drive on the computer hasn't got any more room and I can't really move things around that easily or practically. (sadly modern cameras like to have 1001Bajillion MP in them which makes for huge RAW files).

Besides being slower connection overall, how so?

I've personally had severe problems with USB 3.0 across several PCs, when trying to use it heavily (like copying 100 gigabytes of data from one external HDD to another, over one USB 3.0 port: it starts fine and fast too, but after awhile just stops and usually loses the hard drive, as if the USB port resets itself under heavy load or something).

Doing the same over USB 2.0 was much slower, but fully reliable, never failing the same way.

By googling, it seemed quite often the default USB 3.0 drivers that come with Windows 7 were crappy, they might have been the culprit. At some point I took some suggestion and downloaded other USB 3.0 drivers straight from Intel homepages, but I think I had some issues after that too.

Well the slower connection was the problem here, and thats why i said it.
Personally as some others said i would never use an external to install games as if you lose the connection it can go wrong.
A 1 or 2tb internal aren't so expensive, and just use that.

I considered the actual problem being the installation stalling, and running out of memory(?). I presume that is some kind of a reliability problem, not a speed problem.

I personally wouldn't do that either, for performance reasons, and not knowing what the game installation will react if the external HDD is disconnected and it cannot find it.

As other said, installing programs ON the external HD is a bad idea because it's just slowing things down and unpredictable things can happen. Installing FROM the external HD is no problem.
My HD-space saving strategy for GOG-games I'm not going to play instantly is:
downloading 'em, moving 'em to the external HD and installing from there to my internal HD.